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MG MGF Technical - Anyone tried Splitfire plugs in their F?

... or other high performance spark plugs? Let me know your experiences as my car's in for a new set soon!

Doc Bell, think this one is for u ...

Another snake-oil product to be put in the bin along with Slick 50 and assorted 'fuel catalysts'. Well OK, unlike these other worthless products at least Splitfire plugs do perform a function by providing a spark, it's just that they don't do it any better than a new standard manufacturer-recommended plug.

In the latest in a series of FTC cases targeting deceptive ads for products
that promise to improve automobile performance and economy, SplitFire, Inc.,
has agreed to settle Federal Trade Commission charges that economy,
efficiency and improved performance claims for its spark plugs were false or
unsubstantiated. The agreement to settle the FTC charges will bar SplitFire
from making deceptive claims about fuel economy, emissions, horsepower or
cost savings. The company also will be barred from misrepresenting the
results of tests, studies or research and from misrepresenting testimonials.
SplitFire, Inc., is a Northbrook, Illinois-based marketer of nationally
advertised, premium priced spark plugs that feature a v shape it terms,
"split electrode."
SplitFire advertises that use of its patented spark plugs results in
significantly better fuel economy, greater horsepower, lower emissions and
cost savings than use of either conventional spark plugs or platinum-tipped
spark plugs. According to the complaint detailing the FTC charges, SplitFire
ads stated:
"Equipped with conventional spark plugs, up to 15% of the combustion cycles
in a modern engine end up in 'partial misfires.’ SplitFire’s larger flame
kernel helps reduce partial misfires, and experts say it helps improve:
Performance, Economy, Emissions." and
"It only costs more 'til you use It," and;
"SplitFire conducts continuous consumer surveys to constantly monitor 'real
life’ performance in all vehicle types. . . 70% reported a gas mileage
increase of from 1 to 6 more miles per gallon."
The SplitFire ads also featured consumer endorsements making claims such as,
"They’ll pay for themselves, basically, in the first 6 months you own 'em,"
according to the FTC complaint.
The FTC alleged that SplitFire did not possess and rely upon a reasonable
basis to support the claims, that SplitFire’s claims that surveys confirm
gas mileage increases were false, and that Splitfire did not have a
reasonable basis to claim that the testimonials used in its ads reflect the
typical or ordinary experience of consumers who use SplitFire spark plugs.
The consent order to settle the charges would prohibit SplitFire from making
fuel economy, emissions, horsepower or cost savings claims without competent
and reliable scientific evidence to support them. It would also prohibit
misrepresentations about the existence, contents, validity, results,
conclusions or interpretations of any test or study. Finally, in connection
with testimonials, the settlement would require that SplitFire have
scientific evidence to substantiate claims in endorsements or testimonials;
that Splitfire disclose what the typical or ordinary consumer experience
would be; or that the company disclose the limited applicability of the
endorser’s experience -- that is, that consumers should not expect to
experience similar results.
The Commission vote to accept the consent agreement for public comment was
5-0. The proposed agreement will be placed on the public record for a 60-day
public comment period. Comments should be addressed to the FTC, Office of
the Secretary, 6th Street and Pennsylvania Avenue, N.W., Washington, D.C.
NOTE: A consent agreement is for settlement purposes only and does not
constitute an admission of a law violation. When the Commission issues a
consent order on a final basis, it carries the force of law with respect to
future actions. Each violation of such an order may result in a civil
penalty of $11,000.

Copies of the complaint, consent agreement and a consumer alert, "Penny wise
and Pump Fuelish," are available on the Internet at and
from the FTC’s Public Reference Branch, Room 130, 6th Street and
Pennsylvania Avenue, N.W., Washington, D.C. 20580; 202-326-2222; TTY for the
hearing impaired 202-326-2502. Consent agreements subject to public comments
also are available by calling 202-326-3627. To find out the latest news as
it is announced, call the FTC NewsPhone recording at 202- 326-2710. FTC news
releases and other materials also are available on the Internet at the FTC’s
World Wide Web site at: (no period).
Claudia Bourne Farrell
Office of Public Affairs
Laura Fremont
San Francisco Regional Office
901 Market Street, Suite 570
San Francisco, California 94103
(FTC File No. 952 3029)
Mike Bees

I honestly can not believe that there is much improvement to be had above and beyond what is already a high quality multi-electrode spark plug that all our MGs are fitted with as a standard fit.

I have some K&N sparkers to try outsometime- and I shall- but only against brand-new standard items. Need time at a rolling road really.

I reckon if you fitted new spark plugs on your car you'd feel a difference- but is that because they are new or because they are better?

The above is very interesting- thanks Mike. Just goes to show...

Rob Bell

If you can get hold of an old Merlin engine you can get three sets of plugs out of it :-)

Installed Beru Silverstone plugs in my 96 1.8i. This uses silver instead of platinum as its electrode. I can't say of any power increase but engine response is very good. I changed from the original champions with 24K km on the clock and now 28K km later, the plugs still looked fine.

FYI, the plug number is S3F & it is not the resistor type. Will it cause any side effects on the engine?


I think you will find the thread refers to spLitfire plugs not spitfire:-)

Ted Newman

Thanks Ted, just checking to see if you were paying attention :-)

As Rob so correctly points out any comparison of used plugs against new, even with less than 1000 miles use, is going to provide a completely false result.

Peak performance of a plug demands that it has very sharp edged electrodes in use these are erroded away and then the voltage required to 'jump' the spark increases. Multi earth electrode plugs give the advantage of several points for current to 'jump' rather than just two. This means it maintains performance peaks for longer. The precious metal plugs have a greater resistance to errosion hence the longer service change points, but as many will know already I personally have no faith that the standard K series platinum plugs are any good after about 20k miles. Certainly they will not be anywhere near peak performance.

As a further interest point I still have a preference to NGK that is based on years of actual experience when there was a gain to be had from different makes of plug. The best difference I saw was just short of 20bhp between new NGK and new Unipart.

In recent years though I have been unable to see any difference at all between the main well known and available plugs makers products. This also applies to Splitfires, and here I am being generous since I have seen these give reduced power, only slightly reduced (3bhp) but confirmed as the power was regained by refitting the standard and then lost again with the splitfires.

Based on a perforemance per pound spent basis, these sort of items have to be the worst possible investment. Except when viewed from the sellers perspective!!

Roger Parker

I have Bosch Super 4 sparks fitted to Scarlet about 40.000 miles ago. I'm expecting to replace them this year as i also feel that sparks peak & then go off the boil quite soon. Anyway, i didn't fall for any advertising hype about increased performance or larger sparks being produced, the reason i have super 4's is purely for longevity. In that as one electrode corrodes, the spark then jumps to the next nearest one - electricity always choosing the shortest route/route of least resistance. In this way i believe that you get better performance for longer from multi electrode plugs & would recommend them to anyone.

Scarlet Fever

This thread was discussed between 13/02/2001 and 16/02/2001

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